Subtract 42/12 from 21/8
1st number: 2 5/8, 2nd number: 3 6/12
21/8 - 42/12 is -7/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 12 is 24
Next, find the equivalent fraction of both fractional numbers with denominator 24 - For the 1st fraction, since 8 × 3 = 24,
21/8 = 21 × 3/8 × 3 = 63/24 - Likewise, for the 2nd fraction, since 12 × 2 = 24,
42/12 = 42 × 2/12 × 2 = 84/24 - Subtract the two like fractions:
63/24 - 84/24 = 63 - 84/24 = -21/24 - After reducing the fraction, the answer is -7/8
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